A generic script for text processing originally written specific to some usecases around wiki text.

wiki_helper.py

# -*- coding: utf-8 -*-

__author__ = 'Arun KR (kra3)  <the1.arun@gmail.com>'
__license__ = 'Simplified BSD'

import sys

""" 
wiki_helper.py rules.txt data.txt > result.txt

rules.txt could be any text file with one rule per line.
A Rule will be of format CODE :=> STRING`

CODE will be one of DL or RM. 
DL for delete matching line - PS: matching starts from begining affter removing whitespaces.
RM for remove matching strings from a line.

You have to redirect output to a file or another unix command for further processing.
Utility developed for malayalam wikibooks maintainers.
"""

def wiki_helper(data, rules):
  # list of rules
  delete_line_matches = []
  remove_string_matches = []
  
  # Open files
  data_fh = open(data)
  rules_fh = open(rules)
  
  ## extracting user defined rules
  for line in rules_fh.readlines():
    rule = line.split(':=>')
    
    if len(rule) != 2:  # safegaurd against malformed rules.
      continue
    
    code, expr = map(str.strip, rule)  # strip down her out of whitespaces
    
    # circus to put rules at their places.
    if code == 'DL':
      delete_line_matches.append(expr)
    elif code == 'RM':
      remove_string_matches.append(expr)
    else:
      pass

  ## processing data with rules
  for line in data_fh.readlines():
    matched = False  # sentinel
    
    # loop until a match for delete line is found, 
    # set sentinel and be out as fast as you can.
    for match in delete_line_matches:
      if line.strip().startswith(match):
	matched = True
	break
    
    # remove all those junk to become a slim beauty.
    if not matched:
      for expr in remove_string_matches:
	line = line.replace(expr, '')
      
      # Now, Go; take on the world...
      print line,
	  

if __name__ == '__main__':
  if not len(sys.argv) == 3:
    print "Incorrect format. Try:"
    print "\twiki_helper.py rules data"
    exit(1)
   
  wiki_helper(sys.argv[2], sys.argv[1])

rules.txt

DL :=> {{കേരളത്തിലെ പക്ഷികളുടെ പട്ടിക - തുടക്കം|നിര=
RM :=> {{കേരളത്തിലെ പക്ഷികളുടെ പട്ടിക - ഉള്ളടക്കം|
RM :=> }}